pre {
    background: #F8F8F8;
    border-radius: 2px;
    margin-bottom: 17px;
    padding: 10px;
    overflow: auto;
    position: relative;
    .code-copy {
        position: absolute;
        display: none;
        top: 10px;
        right: 10px;
        padding: 0 10px;
        border-radius: 2px;
        font-size: 20px;
        color: #838586;
        cursor: pointer;
        &:hover {
            color: cadetblue;
        }
    }
}

pre:hover .code-copy {
    display: block;
}